


For The Halibut

by TheGoblinJester



Category: Supernatural
Genre: Alternate Universe - Merpeople, Destiel Ficlet Challenge, Human Castiel, Human Gabriel, M/M, Mermaid Dean, Pre-Relationship, mermaid sam
Language: English
Status: Completed
Published: 2015-11-15
Updated: 2015-11-15
Packaged: 2018-05-01 18:02:45
Rating: Not Rated
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 4,517
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5215382
Author URL: https://archiveofourown.org/users/TheGoblinJester/pseuds/TheGoblinJester
Summary: <blockquote class="userstuff">
              <p>Dean's really only helping Sam out on account of he's family. He doesn't really care for, trust, or remotely like humans.</p>
            </blockquote>





	For The Halibut

“I'm on a boat.”

“Gabriel, if you say that one more time, I'm pushing you overboard.” Castiel promised, not looking up from his laptop.

“Look at your laptop. Now back to me. Now back at your laptop. Now back to me. Sadly, your laptop is not me, but if-”

“Shut the fuck up.”

 

“Remind me again why you need my help with this?” Dean asked, floating lazily on his back alongside Sam, who was etching hastily in his field log. “Hardly seems like a two-person job...”

“Shut up, is why.” Sam told him distractedly, glancing up from the journal to check their distance from the surface. “You're only here because they won't let you do up-close research on humans if you're alone. It's too dangerous.”

“Seems to me, if you're stupid enough to get caught by a human, then you _deserve_ to be turned into sashimi.” Dean grumbled, but obediently took the satchel that Sam thrust into his arms.

“Humans aren't stupid, Dean. They've come up with the most remarkable technology over the past few years...”

“So? Just because they're nerds doesn't mean they can't also be idiots.” Dean reminded him. “Need I remind you of the oil spill? The pollution? The over-fishing? Wait, these guys here ain't fishing, are they?”

“Like I'm that reckless?” Sam scoffed. “No, I think they're doing some research on the sea life in this area. Maybe it has to do with the declining sardine population?”

“Wow, that sounds _exciting._ ”

“Shh. Hand me a new slate, will you?”

“We haven't even gotten there, and you've used up a whole slate?” Dean asked, turning over so he was right-side up.

“I needed an introduction.” Sam said dismissively. He glanced up and spotted the dark figure floating dead ahead in the water, bobbing with the waves. “There it is!”

They swam up to the boat, taking care to stay out of sight from any humans who might glance over the edge. Sam had timed their visit to coincide with the human's midday meal, when they would be distracted by food and probably wouldn't notice any errant merman observing them.

Once they were within arm's reach of the bottom of the boat, Sam motioned to Dean that he was going to boost himself up the side and have a look around. Dean wrinkled his nose but nodded his understanding.

Dean didn't like this. It all seemed so... unnecessarily dangerous. Like, “oh, let's take a nice, close look at our biggest threat in the world! Never mind that they have the upper hand on land and technology that could kill me in an instant, let's find out every mundane detail about their lives!” was a smart way to go about things.

But, of course, he was doing this for Sam. Dumb little brother and his dumb Humanology 101 course that wasn't even required for his major. Sam was studying Deep Sea law, the weirdest kind of law. The merpeople from down in the trenches were something else entirely, and had absolutely nothing to do with humans.

Sam was taking this course because dad hated humans, and this was his own personal rebellion. Dean understood that, but that didn't mean he still didn't think it was dumb. And dangerous.

A school of green Chromis swam by, shimmering gently in the filtered sunlight. Dean stuck out his arm and wiggled his fingers in the midst, causing them to disperse and regroup a couple times before moving on. He kept an eye on Sam, who had pulled himself so far out of the water that only half of his tail remained visible below the surface. Kid sure was taking his sweet time.

Finally, Sam let go of the boat and dropped back into the water. He had something clutched in his hand. Dean swam over to him and clapped him hard on the back.

“Whatcha got there?” Dean asked as Sam held it up to examine the thing.

It was a small rectangle, yellow and black in color and had something like a flattened fish eye in the center.

“I think it's a camera.” Sam replied, grinning and turning it over in his hands. “It captures images, I think, and this one's waterproof. It says so on the side.”

Dean didn't even bother looking at the human runes stamped on the thing. None of their languages were particularly interesting. He watched with reluctant curiosity as Sam pressed a couple raised bumps on the surface of the rectangle - “Buttons,” Sam called them. Dean wasn't sure which one did it, but the rectangle lit up and Sam beamed.

“Wow...” Sam breathed. He held the camera up to his face, fish eye pointing at Dean, and pressed the biggest button. The fish eye flashed with a bright light, startling Dean into jolting backwards, but Sam didn't seem worried. “Look, it's you!”

Dean swam back over to Sam to take a look at the damn thing. Sure enough, in a very small square, there was an image of Dean looking nonplussed.

Sam looked up at Dean expectantly, probably hoping for mirrored excitement. Dean frowned.

“Are the humans gonna realize this is missing?”

“I'll put it back.” Sam assured him.

Dean stared at him, not sure how the genius little brother didn't make the obvious connection.

“What?”

“Sam, you realize that if the humans see this,” Dean gestured at the image, “we'll all be exposed, right?”

“I'm sure there's a way to-”

“There's no reasoning with them, Sam. We're too different, and there's no way to hide from them once they find out about us.” Dean explained. “You know what happened to mom.”

“Dean...”

But Dean snapped the damn rectangle in half.

“Dean!”

“It had to be done!”

“You sound just like dad.” Sam accused.

“That picture could have caused the deaths of thousands!”

“For fucks sake, Dean, it could have been deleted!” Sam grabbed one of the halves of the camera before it could float away, and pointed out a button. “See? That's how you erase the damn pictures!”

“... oh. Um, I guess that's what I get for not choosing English as an elective?”

Sam closed his eyes and sighed heavily. He looked up at Dean, trying to decide what to do. Dean squirmed uncomfortably under the steady wave of brotherly disappointment he was receiving.

“You know what, this is _your_ problem now.” Sam said, handing Dean the half he had grabbed and swimming down to retrieve the other one, which he also gave to Dean. “And to answer your earlier question, yes. This _is_ something they'd miss.”

Sam folded his arms and stared Dean down, glaring until Dean relented and started swimming up to the side of the boat. Stupid camera. Stupid humans. Stupid Dean.

Dean had been above the surface before, of course - It was a common practice to take girls out to stargaze on rock outcroppings where seals hung out – but this was different. Much different.

Camera halves in one hand, Dean reached out with the other and pulled himself up to the edge of the boat. Staying low and mostly hidden, Dean looked around. There was a lot on the boat he didn't really understand. Not that he cared to understand what humans entertained themselves with. There was a raised section in the middle that probably sheltered an area where the humans slept. There was also a large box nearby, and that was where Dean decided to leave the camera.

Unfortunately, it was sitting half a tail's span away, so Dean had to push himself up onto the side and lean as far forward as he could, relying on his tail as counter balance. He reached out, praying to every remotely godlike thing he knew of that he wouldn't fall forward.

And then a seagull landed on the box.

“Shoo!” Dean hissed at it.

It quirked its head to the side, pooped, and then took off.

Dean's shoulders slumped with relief.

He was about to drop the camera pieces on the box when someone grabbed his arm.

Instinctively, Dean twisted and tried to pull away, but the human's grip on his wrist was strong, and Dean was, quite literally, a fish out of water. His heart thudded in his chest, stomach churning and breath catching. This was it, this was the end of him, and all because of a stupid seagull.

The human was making noises, sounding more pissed off than anything. He hadn't seen Dean's tail.

Dean looked up at it.

He – well, the human _appeared_ male, but maybe they had different secondary sex characteristics than merpeople, and even those weren't very reliable – had dark, messy hair that looked black, but glowed brown under the sun. If humans aged like merpeople did, then this one wouldn't be too much older than Dean. He looked a little haggard, a little tired, but sharp and alert.

On the human's wrist was a strange bracelet made of some silvery metal, with a circular piece sitting just below the back of his hand. It had little sticks in it that moved rhythmically. It was the sort of device that Sam would kill to examine.

His legs! His legs! Easily the weirdest thing about humans were the legs. They were wrapped in a dark blue material and ended in strange, leathery things. They were shorter than a tail would be, but not disproportionate-looking.

His eyes were blue.

Dean blinked out of his reverie. This was no time to get distracted, no matter how weird humans looked with their legs and stuff. If he played his cards right, there was a very simple way out of this situation.

Playing as if he too were human, Dean gave a sheepish grin. Then he made like something caught his eye. He quirked his head to the side and stared in confusion at a point beyond the human's shoulder.

The human turned to look.

Wasting no time, Dean ripped away from the human's grasp and let himself fall back into the water. He heard the human give a startled shout, and another human rush over to check out the commotion. Dean didn't stick around.

Propelled by adrenaline, he swam right into Sam, sending them both into a school of anchovies.

“Dean! What happened?”

“Oh, wouldn't you like to know!” Dean laughed, giddy with the relief of not being smoked and eaten with a bagel. “I just _bet_ you'd like to know!”

“Yes, I would!”

“Oh, OK. I'll tell you.” Dean said, terror forgotten as he settled into the age-old role of storyteller. “There I was, returning the dumb rectangle thing-”

“Camera.” Sam interjected.

“Yeah, like I said, the dumb rectangle thing.” Dean nodded. “There I was, anyway, putting it down with care and respect – you would have been so proud of me, you moral freak – when a human grabs me by the arm!”

“Really?”

“You bet your tail fin! I don't think he saw my tail, but it was only a matter of time and he looked angry. I'm talking angrier than Ellen was when she found out Jo got into a fight with a sea elephant. I was staring down the face of certain death. Literally. And you know what I say to death?”

“Something stupid, no doubt?”

“'Not today.' That's what I say to death.” Dean continued, as if he hadn't heard Sam. “So I totally kicked his ass and made it back here without a single scale lost. And just think, Sammy, if I had died up there, whose fault would it have been?”

“Your own.”

“That's right, yours!” Dean said with a grin. “Lucky for your conscience, I'm not completely useless in a tussle.”

“Uh-huh.” Sam had that petulant little brother look for a moment, then seemed to remember that he was actually geeking out. “The human! What was it like? Did it say anything?”

“Well, I think he was male. He had legs and stuff, you know. Human things.” Dean shrugged. “He had this thing on his wrist...”

“A watch. Was he wearing shoes? Did he have a phone? Did he say anything?” Sam asked, previous crossness with Dean entirely forgotten. “Did he hurt you? Did you hurt him? Was it the camera he was mad about, or was it the trespassing? Did he-”

“Whoa, take a deep breath, Sammy.” Dean said. “I wasn't exactly paying attention, you know. I was more concerned about escaping with my life.”

“I've been studying these ones from a distance, Dean. They're not fishermen. They're just doing research, like me.” Sam told him. “I don't think we have much to fear. Wow, an up-close encounter! Now I wish I had gone up instead... what else did you notice?”

“Uh, he kinda yelled at me. Like this.” Dean tried to imitate some of the noises the human had made, but then broke up laughing, because English was just that ridiculous.

Sam scrunched up his nose and looked thoughtful for a moment.

“Something about the camera... I think he was pissed at you for breaking it. Maybe it was their only one?” Sam theorized. “Maybe it can't be fixed... maybe they need it...”

“Sam, no. We're done with the camera. We returned it, and now we're never going to think about it again.” Dean instructed him. “No use crying over whale carcasses, man.”

“I know, but... what if we put them out of a job? What if they had important pictures on there?” Sam asked, frowning. “We should at least try to make up for it.”

“If I show my face up there again, they'll kill me!”

“I'm not talking about hand-delivering anything.” Sam reassured him. “Just, a little something to show we're sorry?”

“Fine, but this time, you're coming up there with me.” Dean relented. Sam beamed at him.

They swam in circles for a bit, deep in thought.

“What do humans like?” Dean asked. “Sea cucumbers?”

“No, I don't think so... coral?”

“Too fragile.” Dean said dismissively. “Driftwood?”

“Too common.” Sam replied. He rubbed his temples, brow furrowed. “Um, let's see if I can remember what goods they get from the ocean... fish... seaweed... oysters... oysters!”

“Oysters? Don't those get kinda smelly out in the air?” Dean asked, wrinkling his nose.

“Not the oysters themselves; what's in them!” Sam said brightly. “Pearls! Humans love pearls!”

“Aren't those just fancy sand grains?”

“Yeah, but who are we to question the whims of man?” Sam asked with a shrug. “They like the blue ones the most, because they're the rarest.”

“Alright. Let's check our nests. I'm pretty sure I keep some pearls around for shooting games.” Dean suggested. Sam nodded his agreement, and they swam home together.

 

Before the crack of dawn, they regrouped under the boat. They each had a small handful of blue pearls and, in Dean's case, a growing sense of dread. They put the pearls in a little bag that Sam carried, and decided that the humans could have that, too.

“This will be quick and easy.” Sam assured him, using his little brother senses to pick up on Dean's anxiousness. “We go up, put the pearls down, and leave. And with both of us watching the other one's back, there's no way the humans will get the drop on us.”

“I know, I know. Quit fussing.” Dean complained. “Let's just get this over with.”

“This is the right thing to do, Dean.” Sam said solemnly. Dean just nodded silently. They swam up to the side of the boat and prepared to grab onto the side. After they were both in position, Dean counted down from on his fingers, and when he hit one, they pulled themselves up and over.

The boat wasn't much different at night. A bit spookier, but what _wasn't_ spookier at night. Dean looked to the right as Sam did the same to the left. All clear. Sam, who had longer arms, reached out and dropped the bag on the same box where Dean had left the camera, avoiding the seagull poop.

“There. We're done.” Sam whispered.

And then the lights came on.

“Time to go!” Dean hissed. He made to go, but stopped when he noticed Sam hadn't budged. “Sammy! Get your rear in gear!”

It was too late. The humans emerged from the raised square thing in the center of the boat and had their eyes locked on the mermen. One barked something. Dean tugged at Sam's shoulder, but the damn guy was watched them with rampant fascination.

There were two of them. One, whom Dean recognized as the human who had grabbed him earlier, was taller than the other. The shorter one was watching them with wide eyes and a disbelieving grin spreading on his face, whereas the taller one stared with his brow furrowed and gaze wary.

The tension was thicker than seal blubber.

And then Sam gave a sheepish smile and waved at them.

“Sam, what the fuck?” Dean demanded, trying to pull his brother back towards the water.

“He asked us not to go.” Sam replied.

 

“Hello! My name is Sam, and this is my...” the merman quirked his head to the side, as if trying to remember something. “Brother? Brother. This is my brother, Dean.”

Castiel and Gabriel's jaws dropped.

“You speak English!” Gabriel said dumbly.

“A little.” Sam said, raising a hand and holding his fingers a half-inch apart to indicate his adeptness with the language. “I am still... learning.”

Castiel and Gabriel nodded slowly.

The other merman – Dean – was whispering something to Sam, never taking his suspicious gaze off Castiel and Gabriel. Sam replied in kind, perhaps admonishing him.

“Well, er, gentlemen, why don't you... make yourselves comfortable?” Gabriel suggested, with a hint of the manic fervor he emanated in situations he was desperately trying to make sense of. “Can't be comfortable, supporting yourself on the starboard side of the ship like that!”

“Excuse me?” Sam said, narrowing his eyes. Gabriel was anything but a slow talker.

“You can come on board, if you want.” Castiel clarified.

Sam blinked, then turned to his brother and said something quietly. Dean looked aghast and shook his head. They continued in this manner until Sam pulled the kind of ridiculous puppy face Gabriel would use to get his way; except on Sam, it was actually effective. Dean heaved his shoulders in a sigh, but followed suit as his brother swung his tail around so he was sitting on the railing.

Tails! Shimmering, powerful tails, with enormous, fanning fins on the end. Sam's was all shades of blue and green, mottled and changing depending on how the light caught it. Dean's was a brilliant emerald, edged with warmer tones and glittering softly under the dim lighting.

“I'm sorry for my brother. He is... not trusting humans.” Sam explained.

“And you are?” Castiel asked dubiously.

“I am doing research.” Sam said seriously. “And my research shows that you don't have a camera to take pictures of us, so no one will believe you saw us.”

“Well, actually...” Gabriel produced his phone and pulled up an image. “We managed to retrieve our pictures from the camera _he_ broke.”

It had been rather shaking when they found that photo. Gabriel was convinced it had been some elaborate prank, and since he was the master of pranks, Castiel listened to his theory. It had been the same guy who returned the broken camera, anyway, so there wasn't much to dispute Gabriel's idea.

Seeing the look on both of the mermen's faces, Castiel took Gabriel's phone and deleted the picture.

“Hey!” Gabriel protested. Castiel ignored him.

“There, see? It's gone.” Castiel said, holding up the phone for them to see. Sam seemed appeased, but Dean still looked somewhat murderous. “I promise, we're not a threat.”

Sam relayed this to Dean, who relaxed maybe the tiniest bit.

 

“Holy shit, Castiel, look at all these fuckin' blue pearls!”

 

Two weeks later, and Gabriel and Castiel had finally somewhat gotten over the shock over the new-found existence of mermaids, and Dean had given up on caution and was now attempting friendship.

Castiel suspected that what finally tipped Dean over into friendliness territory was the slice of pie he had been offered about a half-week after they first met. That was most likely the exact moment that Dean decided that humans probably weren't _that_ bad.

 

“You know what, forget it.” Dean scowled, rubbing his head. “I just wasn't made to speak English, you know? Just like you weren't made to be any semblance of cool.”

“Dude, you're doing fine.” Sam said, albeit with a note of exasperation. “Be patient, alright?”

“I don't have time for patience.” Dean grumbled.

Castiel and Gabriel's research trip would end in three weeks.

“Come on, imagine the looks on their faces when they find out.” Sam implored him. “You know what, I think Gabriel thinks you're too parrot fish to actually learn English.”

“He does? Fuck that guy!”

“It's on the agenda. And you'll totally impress Cas! He's sort of a linguistics nerd, anyway. I bet he'd like to learn Mermish from you.”

“Shut up. Also, what's this about an agenda?”

 

“Hello, Dean.” Castiel said with a smile.

Dean recognized those words, he noticed with a hint of pride, but he wasn't going to let that on just yet.

“You know, we've been buying even more pie than usual lately... I wonder why that is...” Castiel continued, pushing a plate with a hefty slice of pecan pie on it towards Dean.

Dean pulled himself over the side of the boat and sort of slopped down on one of the extra deck chairs that had been brought out for him and Sam. The concepts of “sitting down” for a meal and eating with “forks” were entirely new to him, but if that was custom... well, when in Rome, as the humans might say!

Dean had no idea what Rome was, but he thought he got the context.

“It's rather humbling, I must admit, to learn of a species equal to, perhaps even above, or own, in terms of intellect.” Castiel remarked.

…

Dean understood about eighty percent of that, which was much better than usual. Gabriel talked fast, but Castiel talked _complicated._

 

While Gabriel had eyes that reflected sunlight like amber sea glass, Castiel had eyes that birds could soar through. For the first time in his life, Dean found himself appreciating the color of the sky.

 

Castiel brought out a book about humans one day. How their muscles, legs, lungs and digestive systems worked. Dean didn't find it particularly interesting, but Sam took enough notes to fill seven slates.

“I'm going to get a hundred and eleven score on this report.” Sam breathed happily.

 

“I can't believe we only have one week left.” Gabriel lamented one morning. “I'm going to miss those dorks...”

“... yeah.” Castiel agreed.

 

They were sitting on the rocks where the seals hung out, and Dean was giving up.

“Seriously, Sam, I can't do this.” Dean insisted. “I'm the brawn, _you're_ the genius.”

“Dean...”

“Look, they're gonna leave anyway, so what's the point?” Dean demanded. “They're gonna go away, and we're never going to see them again. That's that.”

“ _Dean._ ”

“And sure, you got a good research paper on them, but there was literally _no point at all_ to me trying to learn English. I'm not even sure why the hell we thought that would be a good idea.” Dean shook his head and let out a sigh. “I appreciate the effort, I really do, but it's hopeless. I'm never gonna get to talk to him- _them._ I'm never gonna get to talk to them. So what? Who cares?”

“Dean.”

“Sammy, it's fine. I'm fine.” Dean assured him. “Really, I don't care. You got your final all written up, they got their article on declining sardine populations, and I got some pie. It's all good.”

“Deeaan.”

“I don't know why you're making this such a big deal, anyway. It's not a big deal. Really, Sam-”

“DEAN.”

Dean paused.

“Yeah?”

“You've been speaking perfect English for the last five minutes.”

Dean blinked.

“Oh.”

“Um, yeah. Dude, you're ready.”

 

“Done. Your punctuation was all over the place, but overall, it's a solid story.” Castiel declared, hitting control + s on his laptop.

“A solidly boring story. Who cares about sardines?” Gabriel lamented.

“You've been spoiled. Just because merpeople exist doesn't mean we're about to get interesting assignments any time soon.” Castiel told him.

“Shame we can't, ethically, write about _them._ ” Gabriel remarked. “Someday... the world will be ready...”

“That's what you said about S'moreos Cheerios, and that was ten years ago.”

“S'moreos Cheerios are just too intense an experience for the modern man to handle.” Gabriel said dismissively. “I tell you, brother of mine, when the time is right, I'll be rolling in the dough like a S'moreos Cheerio gets rolled in marshmallow stuff and chocolate!”

“I'm getting cavities just hearing about it.”

They were distracted from their intellectual debate by Sam and Dean pulling themselves up to the side of the boat.

“Hey, guys! Make yourselves cozy!” Gabriel said with a grin, kicking the chair nearest him towards Sam. “We just finished writing our article. I'm... not actually sure why we had to be on a boat to do it, but damn did we get some nice pictures of sardines! At least, we did before our camera was destroyed.”

Sam sat himself in the chair, but Dean stayed where he was. Castiel looked at him questioningly. Dean raised an eyebrow and nodded away from their respective brothers, towards a quieter part of the boat. Castiel shrugged and got to his feet, following Dean over a ways to the stern.

“Well, I suppose this is goodbye...” Castiel said stiffly. He had never been good at this sort of thing. “I regret that we did not get to know each other better, due to cultural and language barriers...”

Castiel coughed and offered his hand for Dean to shake.

Dean looked up at him.

“You know, I'd ask for your number, but I seem to have misplaced my _shell phone._ ”

 

Sam and Gabriel were startled from their intriguing conversation about the merits of those weird-ass fish what live deep in the oceans by an eruption of what sounded like startled laughter.

Two people laughing, as a matter of fact.

Castiel, wiping away _actual tears of mirth,_ made his way back over to the deck chairs, while Dean dropped back into the water and swam over. The merman pulled himself up over the side and onto one of the aforementioned chairs, grinning stupidly.

“Gabriel, you won't _believe_ what just happened.” Castiel gasped, trying to compose himself. “Of all the horrible puns...! And pick-up lines, too, for that matter!”

Gabriel looked at Sam helplessly, having no idea what was going on. Sam merely shrugged.

“Are... are you OK, Cas?” Gabriel asked gently.

“I'd say he's having a whale of a time.” Dean chimed in.

Gabriel fell out of his chair.

Castiel started laughing again.

“Humans are crazy.” Sam said, shaking his head with an amused sort of smile.

“Nothing to be done about that.” Dean replied, unable to wipe the grin off his face.


End file.
